In general, a solid oxide fuel cell (SOFC) comprises a pair of electrodes (anode and cathode) separated by a ceramic, solid-phase electrolyte. To achieve adequate ionic conductivity in such a ceramic electrolyte, the SOFC operates at an elevated temperature, typically at a minimum of 750° C. and usually in the order of about 1000° C. The material in typical SOFC electrolytes is a fully dense (i.e. non-porous) yttria-stabilized zirconia (YSZ) which is an excellent conductor of negatively charged oxygen (oxide) ions at high temperatures. Typical SOFC anodes are made from a porous nickel/zirconia cermet while typical cathodes are made from magnesium doped lanthanum manganate (LaMnO3), or a strontium doped lanthanum manganate (also known as lanthanum strontium manganate (LSM)). In operation, hydrogen or carbon monoxide (CO) in a fuel stream passing over the anode reacts with oxide ions conducted through the electrolyte to produce water and/or CO2 and electrons. The electrons pass from the anode to outside the fuel cell via an external circuit, through a load on the circuit, and back to the cathode where oxygen from an air stream receives the electrons and is converted into oxide ions which are injected into the electrolyte. The SOFC reactions that occur include:
Anode reaction:H2+O═→H2O+2e−CO+O═→CO2+2e−CH4+4O═→2H2O+CO2+8e−
Cathode reaction:O2+4e−→2O50 
Known SOFC designs include planar and tubular fuel cells. Applicant's own PCT application no. PCT/CA01/00634 discloses a method of producing a tubular fuel cell by electrophoretic deposition (EPD). The fuel cell comprises multiple concentric layers, namely an inner electrode layer, a middle electrolyte layer, and an outer electrode layer. The inner and outer electrodes may suitably be the anode and cathode respectively, and in such case, fuel may be supplied to the anode by passing through the tube, and air may be supplied to the cathode by passing over the outer surface of the tube.
As mentioned, solid oxide fuel cells operate at high temperatures. It is known that decreasing the thickness or increasing the conductivity of the electrolyte will enable the fuel cell to operate at lower temperatures. Reducing the overall wall thickness of the fuel cell has additional benefits, including low thermal mass and increasing the thermal shock resistance of the fuel cell, which contributes to reducing fuel cell start up/shut down time. However, when the fuel cell wall thickness is reduced, its mechanical strength is also reduced. Thin-walled tubular SOFCs tend to be relatively fragile and may not even be self-supporting, which limit their usefulness in commercial operation, especially in conditions that require robust fuel cell components.